Why it Might Work: Her previous talk show, which she hosted for 11 years, as well as her appearance on Dancing With the Stars, have given her something of an installed fan base. And that audience -- which responded to her weight-loss battle -- has matured with her and now faces similar issues, such as divorce, remarriage and raising teens. She has a sophisticated digital and social media strategy that she hopes will expand that potentially loyal fan base.

Why It Might Not: It's unclear just how much of that fan base is going to come back, lo these many years later. Lake's previous show had an overly sensational (some might say low-rent) aspect that could cast a shadow. In the past, 20th TV has been impatient with shows that take too long to build an audience.

Why it Might Work: She has a high profile from her long-running stint co-hosting NBC's Today and (her somewhat shorter stint) anchoring the CBS Evening News, where she increased her journalistic credibility. She can engage newsmakers, celebrities and a diverse range of guests, both elevating the conversation and making it relatable, and can share her personal experiences as a parent and as someone who lost a spouse to cancer.

Why It Might Not: She can sometimes appear condescending to those who are not her intellectual equal. Whether she can drive ratings after her CBS News experience is a question mark. Katie is such an expensive show (with her salary being a large component) that the high expectations may be unrealistic.

Why it Might Work: He has a very affable personality -- burnished through his 13 years hosting Survivor -- and is as open as a child in the way he shares his life experiences. Newly married to a woman with children, he brings the discovery of modern parenthood. He is being backed by a CBS division that has demonstrated an ability to launch shows and keep them on the air.

Why It Might Not: He seems to be all over the place in terms of what he wants the show to be -- at the TCA press tour, he revealed he's all about saying "yes to new adventures." As much as audiences have welcomed him into their living rooms for more than a decade, the people who watch Survivor do so for the competition, not for him, so it's uncertain whether his popularity will translate.

Why it Might Work: She has proved her skills and popularity as a talk show host in the U.K. and Australia; when she guested on (and eventually guest hosted) Maury, the ratings went up. Plus, given that African Americans watch a disproportionate amount of daytime TV, it probably doesn't hurt to be a black woman hosting a talk show.

Why It Might Not: She is doing confrontational talk but in a much softer style -- at times, even spiritual -- than feisty sister shows such as Jerry Springer and Maury, which could backfire. As a foreigner with an accent that can come across as aristocratic, she may find it hard to connect with a working-class audience.

Why it Might Work: He is an established stand-up comedian who brings an audience that has fallen in behind him thanks to his hit movies (The Original Kings of Comedy), best-selling books (Think Like a Man) and TV series (The Steve Harvey Show) including his successful hosting of Showtime at the Apollo and, most recently, Family Feud, where he goosed the ratings. He has a nationally syndicated radio program to use as a promotional tool. His light touch might provide a counterbalance to the more strident hosts like Couric.

Why It Might Not: Harvey's core beliefs are more conservative than might be widely known, which could alienate him from a historically liberal ethnic audience. It's possible that his aformentioned light touch could come off as shallow.